Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a929cbee authored by Dmitry Kasatkin's avatar Dmitry Kasatkin Committed by Herbert Xu
Browse files

crypto: omap-sham - replace flags operation with atomic bit operations 



Some flags are changed in interrupt handlers and verified in the tasklet.
There might be a race condition when tasklet is interrupted or another
cpu/core will run IRQ handler and tasklet in parallel.
Atomic bitops functions are now used instead of bitmask operations.

Signed-off-by: default avatarDmitry Kasatkin <dmitry.kasatkin@nokia.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent ea1fd224

drivers/crypto/omap-sham.c

+13 −16
Original line number Diff line number Diff line
@@ -240,7 +240,7 @@ static int omap_sham_hw_init(struct omap_sham_dev *dd) 
{

	clk_enable(dd->iclk);



	if (!(dd->flags & BIT(FLAGS_INIT))) {

	if (!test_bit(FLAGS_INIT, &dd->flags)) {

		omap_sham_write_mask(dd, SHA_REG_MASK,

			SHA_REG_MASK_SOFTRESET, SHA_REG_MASK_SOFTRESET);
@@ -248,7 +248,7 @@ static int omap_sham_hw_init(struct omap_sham_dev *dd) 
					SHA_REG_SYSSTATUS_RESETDONE))

			return -ETIMEDOUT;



		dd->flags |= BIT(FLAGS_INIT);

		set_bit(FLAGS_INIT, &dd->flags);

		dd->err = 0;

	}
@@ -303,7 +303,7 @@ static int omap_sham_xmit_cpu(struct omap_sham_dev *dd, const u8 *buf, 
		return -ETIMEDOUT;



	if (final)

		ctx->flags |= BIT(FLAGS_FINAL); /* catch last interrupt */

		set_bit(FLAGS_FINAL, &ctx->flags); /* catch last interrupt */



	len32 = DIV_ROUND_UP(length, sizeof(u32));
@@ -336,9 +336,9 @@ static int omap_sham_xmit_dma(struct omap_sham_dev *dd, dma_addr_t dma_addr, 
	ctx->digcnt += length;



	if (final)

		ctx->flags |= BIT(FLAGS_FINAL); /* catch last interrupt */

		set_bit(FLAGS_FINAL, &ctx->flags); /* catch last interrupt */



	dd->flags |= BIT(FLAGS_DMA_ACTIVE);

	set_bit(FLAGS_DMA_ACTIVE, &dd->flags);



	omap_start_dma(dd->dma_lch);
@@ -642,7 +642,7 @@ static void omap_sham_finish_req(struct ahash_request *req, int err) 


	if (!err) {

		omap_sham_copy_hash(req, 1);

		if (ctx->flags & BIT(FLAGS_FINAL))

		if (test_bit(FLAGS_FINAL, &ctx->flags))

			err = omap_sham_finish(req);

	} else {

		ctx->flags |= BIT(FLAGS_ERROR);
@@ -666,14 +666,14 @@ static int omap_sham_handle_queue(struct omap_sham_dev *dd, 
	spin_lock_irqsave(&dd->lock, flags);

	if (req)

		ret = ahash_enqueue_request(&dd->queue, req);

	if (dd->flags & BIT(FLAGS_BUSY)) {

	if (test_bit(FLAGS_BUSY, &dd->flags)) {

		spin_unlock_irqrestore(&dd->lock, flags);

		return ret;

	}

	backlog = crypto_get_backlog(&dd->queue);

	async_req = crypto_dequeue_request(&dd->queue);

	if (async_req)

		dd->flags |= BIT(FLAGS_BUSY);

		set_bit(FLAGS_BUSY, &dd->flags);

	spin_unlock_irqrestore(&dd->lock, flags);



	if (!async_req)
@@ -1037,13 +1037,10 @@ static void omap_sham_done_task(unsigned long data) 
	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);

	int ready = 0, err = 0;



	if (ctx->flags & BIT(FLAGS_OUTPUT_READY)) {

		ctx->flags &= ~BIT(FLAGS_OUTPUT_READY);

	if (test_and_clear_bit(FLAGS_OUTPUT_READY, &ctx->flags))

		ready = 1;

	}



	if (dd->flags & BIT(FLAGS_DMA_ACTIVE)) {

		dd->flags &= ~BIT(FLAGS_DMA_ACTIVE);

	if (test_and_clear_bit(FLAGS_DMA_ACTIVE, &dd->flags)) {

		omap_sham_update_dma_stop(dd);

		if (!dd->err)

			err = omap_sham_update_dma_start(dd);
@@ -1077,7 +1074,7 @@ static irqreturn_t omap_sham_irq(int irq, void *dev_id) 
		return IRQ_HANDLED;

	}



	if (unlikely(ctx->flags & BIT(FLAGS_FINAL)))

	if (unlikely(test_bit(FLAGS_FINAL, &ctx->flags)))

		/* final -> allow device to go to power-saving mode */

		omap_sham_write_mask(dd, SHA_REG_CTRL, 0, SHA_REG_CTRL_LENGTH);
@@ -1085,7 +1082,7 @@ static irqreturn_t omap_sham_irq(int irq, void *dev_id) 
				 SHA_REG_CTRL_OUTPUT_READY);

	omap_sham_read(dd, SHA_REG_CTRL);



	ctx->flags |= BIT(FLAGS_OUTPUT_READY);

	set_bit(FLAGS_OUTPUT_READY, &ctx->flags);

	dd->err = 0;

	tasklet_schedule(&dd->done_task);
@@ -1099,7 +1096,7 @@ static void omap_sham_dma_callback(int lch, u16 ch_status, void *data) 
	if (ch_status != OMAP_DMA_BLOCK_IRQ) {

		pr_err("omap-sham DMA error status: 0x%hx\n", ch_status);

		dd->err = -EIO;

		dd->flags &= ~BIT(FLAGS_INIT); /* request to re-initialize */

		clear_bit(FLAGS_INIT, &dd->flags);/* request to re-initialize */

	}



	tasklet_schedule(&dd->done_task);